Some 13 million people may leave coastal areas by 2100 affecting even landlocked Nevada, Arizona and Wyoming states

By Tom James

SEATTLE, April 18 (Reuters) - Rising sea levels caused by climate change may drive U.S. coastal residents to areas far from the seaboard, not just to adjacent inland regions, according to a study published online in the journal Nature Climate Change.

Even landlocked states such as Arizona and Wyoming could see significant increases in population because of coastal migration by 2100, and may be unprepared to handle the surge, said the analysis from a University of Georgia researcher.

"We typically think about sea-level rise as being a coastal challenge or a coastal issue," Mathew Hauer, author of the study and head of the Applied Demography program at the University of Georgia, said in an interview on Tuesday. "But if people have to move, they go somewhere."

The U.S. National Oceanic and Atmospheric Administration predicted in January a 1-to-8-foot (0.3-2.5 metre) increase in sea levels by the year 2100. Previous research by Hauer and others has put the number of Americans displaced by rising seas over the same period as high as 13.1 million.

While a movement of residents from low-lying coastal regions to adjacent inland communities will likely occur, Hauer said that according to his model, even landlocked states such as Nevada, Arizona and Wyoming will see an influx.

Nevada's Clark County, home to Las Vegas, is projected to see an influx of up to 117,000 climate migrants by the end of the century, and nearly every county in Wyoming is predicted to see some increase, as are many counties in western Montana, central Colorado and northern Utah, the study found.

Hauer said previous studies had shown that people permanently leaving their homes often choose destinations where they have family connections or better job prospects, even if those locations are far away.

"A lot of these places, although they might seem like they're very far (from the coast), people may have kin ties or economic ties or economic reasons for moving," he said. "People could go to school in an area and they come back years later, maybe that's closer to family."

Although municipalities typically are not considering climate migrants in their long-term planning, Hauer said, they should start to do so because the effects of sea-level rise were already being felt.

"It's not like we go from zero feet of sea-level rise to 6 feet right at the end of the century - it's an incremental process," he said. (Reporting by Tom James; Editing by Patrick Enright and Peter Cooney)

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